5de815a7ee
Bsg holding a reference to the parent device may result in a crash if a bsg file handle is closed after the parent device driver has unloaded. Holding a reference is not really needed: the parent device must exist between bsg_register_queue and bsg_unregister_queue. Before the device goes away the caller does blk_cleanup_queue so that all in-flight requests to the device are gone and all new requests cannot pass beyond the queue. The queue itself is a refcounted object and it will stay alive with a bsg file. Based on analysis, previous patch and changelog from Anatoliy Glagolev. Reported-by: Anatoliy Glagolev <glagolig@gmail.com> Reviewed-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
80 lines
2.1 KiB
C
80 lines
2.1 KiB
C
/*
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* BSG helper library
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*
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* Copyright (C) 2008 James Smart, Emulex Corporation
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* Copyright (C) 2011 Red Hat, Inc. All rights reserved.
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* Copyright (C) 2011 Mike Christie
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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*/
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#ifndef _BLK_BSG_
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#define _BLK_BSG_
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#include <linux/blkdev.h>
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#include <scsi/scsi_request.h>
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struct request;
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struct device;
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struct scatterlist;
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struct request_queue;
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struct bsg_buffer {
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unsigned int payload_len;
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int sg_cnt;
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struct scatterlist *sg_list;
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};
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struct bsg_job {
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struct device *dev;
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struct kref kref;
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unsigned int timeout;
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/* Transport/driver specific request/reply structs */
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void *request;
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void *reply;
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unsigned int request_len;
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unsigned int reply_len;
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/*
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* On entry : reply_len indicates the buffer size allocated for
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* the reply.
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*
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* Upon completion : the message handler must set reply_len
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* to indicates the size of the reply to be returned to the
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* caller.
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*/
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/* DMA payloads for the request/response */
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struct bsg_buffer request_payload;
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struct bsg_buffer reply_payload;
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int result;
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unsigned int reply_payload_rcv_len;
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void *dd_data; /* Used for driver-specific storage */
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};
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void bsg_job_done(struct bsg_job *job, int result,
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unsigned int reply_payload_rcv_len);
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struct request_queue *bsg_setup_queue(struct device *dev, const char *name,
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bsg_job_fn *job_fn, int dd_job_size);
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void bsg_job_put(struct bsg_job *job);
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int __must_check bsg_job_get(struct bsg_job *job);
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#endif
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